我有支持iOS和Android的Xamarin Forms应用。它在发布模式下在Android上正常运行。在iOS上，它不在发布模式下工作，但在调试模式下工作。单击一个调用少量功能的按钮时会崩溃。我在下面附上了错误日志。奇怪的是，它在发布模式下可以在模拟器上运行。
错误日志：
Incident Identifier: 391C564C-028D-4084-BC4A-21ED49BB1F25
CrashReporter Key: 30B4418D-AA04-4575-97A3-97A9F491C62D
Hardware Model: iPhone7,2
Process: TestApp.iOS [600]
Path: /var/containers/Bundle/Application/7F4E5392-9BEA-4578-9E23-02112B61EB96/TestApp.iOS.app/TestApp.iOS
Identifier: uk.co.company.testapp
Version: 0.0.1 (1.0)
Code Type: ARM-64
Parent Process: ??? [1]
Date/Time: 2018-01-22T13:02:31Z
Launch Time: 2018-01-22T13:02:23Z
OS Version: iPhone OS 9.3.2 (13F69)
Report Version: 104-Xamarin
Exception Type: SIGABRT
Exception Codes: #0 at 0x180da811c
Crashed Thread: 0
Application Specific Information:
*** Terminating app due to uncaught exception 'System.ArgumentNullException', reason: 'System.ArgumentNullException: Value cannot be null.'
Xamarin Exception Stack:
Parameter name: method
at System.Linq.Expressions.Expression.Call (System.Linq.Expressions.Expression instance, System.Reflection.MethodInfo method, System.Collections.Generic.IEnumerable`1[T] arguments) [0x00111] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/external/corefx/src/System.Linq.Expressions/src/System/Linq/Expressions/MethodCallExpression.cs:1239
at System.Linq.Expressions.Expression.Call (System.Linq.Expressions.Expression instance, System.Reflection.MethodInfo method, System.Linq.Expressions.Expression[] arguments) [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/external/corefx/src/System.Linq.Expressions/src/System/Linq/Expressions/MethodCallExpression.cs:1046
at System.Linq.Expressions.Expression.Call (System.Reflection.MethodInfo method, System.Linq.Expressions.Expression[] arguments) [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/external/corefx/src/System.Linq.Expressions/src/System/Linq/Expressions/MethodCallExpression.cs:1001
at System.Dynamic.ExpandoObject+MetaExpando.BindSetMember (System.Dynamic.SetMemberBinder binder, System.Dynamic.DynamicMetaObject value) [0x00033] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/external/corefx/src/System.Linq.Expressions/src/System/Dynamic/ExpandoObject.cs:863
at System.Dynamic.SetMemberBinder.Bind (System.Dynamic.DynamicMetaObject target, System.Dynamic.DynamicMetaObject[] args) [0x00035] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/external/corefx/src/System.Linq.Expressions/src/System/Dynamic/SetMemberBinder.cs:57
at System.Dynamic.DynamicMetaObjectBinder.Bind (System.Object[] args, System.Collections.ObjectModel.ReadOnlyCollection`1[T] parameters, System.Linq.Expressions.LabelTarget returnLabel) [0x000c6] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/external/corefx/src/System.Linq.Expressions/src/System/Dynamic/DynamicMetaObjectBinder.cs:90
at System.Runtime.CompilerServices.CallSiteBinder.BindCore[T] (System.Runtime.CompilerServices.CallSite`1[T] site, System.Object[] args) [0x00019] in <8bc31b0df50a4d32b3f1d5af764165ad>:0
at System.Runtime.CompilerServices.CallSiteOps.Bind[T] (System.Runtime.CompilerServices.CallSiteBinder binder, System.Runtime.CompilerServices.CallSite`1[T] site, System.Object[] args) [0x00000] in <8bc31b0df50a4d32b3f1d5af764165ad>:0
at (wrapper managed-to-native) System.Reflection.MonoMethod:InternalInvoke (System.Reflection.MonoMethod,object,object[],System.Exception&)
at System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00032] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/mcs/class/corlib/System.Reflection/MonoMethod.cs:305
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:152
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw (System.Exception source) [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:156
at System.Linq.Expressions.Interpreter.ExceptionHelpers.UnwrapAndRethrow (System.Reflection.TargetInvocationException exception) [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/external/corefx/src/System.Linq.Expressions/src/System/Linq/Expressions/Interpreter/Utilities.cs:172
at System.Linq.Expressions.Interpreter.MethodInfoCallInstruction.Run (System.Linq.Expressions.Interpreter.InterpretedFrame frame) [0x00035] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/external/corefx/src/System.Linq.Expressions/src/System/Linq/Expressions/Interpreter/CallInstruction.cs:327
at System.Linq.Expressions.Interpreter.Interpreter.Run (System.Linq.Expressions.Interpreter.InterpretedFrame frame) [0x00015] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/external/corefx/src/System.Linq.Expressions/src/System/Linq/Expressions/Interpreter/Interpreter.cs:63
at System.Linq.Expressions.Interpreter.LightLambda.Run3[T0,T1,T2,TRet] (T0 arg0, T1 arg1, T2 arg2) [0x00038] in <8bc31b0df50a4d32b3f1d5af764165ad>:0
at TestApp.LoginPage+<onLoginClicked>d__1.MoveNext () [0x00205] in <42b3f78eef3b4fad8ca201e1a739e68b>:0
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:152
at System.Runtime.CompilerServices.AsyncMethodBuilderCore+<>c.<ThrowAsync>b__6_0 (System.Object state) [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/11.6.1.3/src/mono/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/AsyncMethodBuilder.cs:1018
at UIKit.UIKitSynchronizationContext+<Post>c__AnonStorey0.<>m__0 () [0x00000] in /Users/builder/data/lanes/5665/f70a1348/source/xamarin-macios/src/UIKit/UIKitSynchronizationContext.cs:24
at Foundation.NSAsyncActionDispatcher.Apply () [0x00000] in /Users/builder/data/lanes/5665/f70a1348/source/xamarin-macios/src/Foundation/NSAction.cs:163
at (wrapper managed-to-native) UIKit.UIApplication:UIApplicationMain (int,string[],intptr,intptr)
at UIKit.UIApplication.Main (System.String[] args, System.IntPtr principal, System.IntPtr delegate) [0x00005] in /Users/builder/data/lanes/5665/f70a1348/source/xamarin-macios/src/UIKit/UIApplication.cs:79
at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x00038] in /Users/builder/data/lanes/5665/f70a1348/source/xamarin-macios/src/UIKit/UIApplication.cs:63
at TestApp.iOS.Application.Main (System.String[] args) [0x00000] in <52e34ea9026340479b8dc6a53c640f1e>:0
修改 我有一个有趣的发现。我只需按一下按钮即可调用onLoginClicked函数，然后调用PostData函数，该函数使REST调用将数据发送到服务器。每当调用PostData函数时，应用程序崩溃。
如果我将所有代码从PostData函数移动到onLoginClicked函数，它就可以工作！
请在下面找到更多信息：
应用程序在调用PostData函数的行中的onLoginClicked方法崩溃，即
string responseData = await PostData（user，＆＃34; auth / login＆＃34;）;
当我尝试在PostData函数中添加一些警报时，看看是什么 指出它到达但发现它甚至没有达到第一个 在那个方法中。这很奇怪。
代码：
async void onLoginClicked(object sender, System.EventArgs e)
{
string error = "";
if (txtEmail.Text == null || txtEmail.Text == "")
{
error += Constants.ERR_BLANK_EMAIL + "\r\n";
}
else if (txtEmail.Text.Length < 6)
{
error += Constants.ERR_EMAIL_LENGTH + "\r\n";
}
else if (!Common.isEmailValid(txtEmail.Text))
{
error += Constants.ERR_EMAIL_VALIDATION + "\r\n";
}
if (txtPassword.Text == null || txtPassword.Text == "")
{
error += Constants.ERR_BLANK_PASSWORD;
}
if (error != "")
{
lblError.Text = error;
errorContainer.IsVisible = true;
return;
}
else
{
errorContainer.IsVisible = false;
}
if (CrossConnectivity.Current.IsConnected)
{
var loadingPage = new LoadingPage();
await Navigation.PushPopupAsync(loadingPage);
var device_token = App.channelId;
dynamic user = new System.Dynamic.ExpandoObject();
user.email = txtEmail.Text;
user.user_type = "b2b";
user.device_token = device_token;
user.password = txtPassword.Text;
if (Device.RuntimePlatform == Device.iOS)
{
user.device_type = "ios";
}else{
user.device_type = "android";
}
string responseData = await PostData(user, "auth/login");
dynamic responseObj = JObject.Parse(responseData);
if (responseObj["error_code"].Value == 0)
{
var data = responseObj["data"];
Constants.user = Common.GetUserObject(data.ToString());
Helpers.Settings.Password = "" + txtPassword.Text;
Helpers.Settings.UserId = "" + Constants.user.userId;
Helpers.Settings.accessToken = ""+data.access_token;
Helpers.Settings.Email = "" + txtEmail.Text;
var outletResp = responseObj["outlet_details"];
var outlet_count = outletResp.Count;
if(outlet_count>0)
{
Constants.outlets = new List<Outlet>();
foreach(var store in outletResp){
Outlet shop = new Outlet();
shop.access_token = store["access_token"];
shop.email = store["email"];
shop.user_id = store["id"];
shop.master_id = store["master_id"];
shop.outlet_id = store["outlet_id"];
shop.post_code = store["post_code"];
shop.profile_pic = store["profile_pic"];
shop.retailer_id = store["retailer_id"];
shop.retailer_image = store["retailer_image"];
shop.store_name = store["store_name"];
shop.tutorial_pricing_tool = int.Parse(""+store["tutorial_pricing_tool"]);
Constants.outlets.Add(shop);
}
}
var isPinSet = Helpers.Settings.PinSet;
await Navigation.RemovePopupPageAsync(loadingPage);
if (responseObj.data.pin==0 || !isPinSet){
App.Current.MainPage = new NavigationPage(new SetPinPage(false));
}
else{
App.Current.MainPage = new NavigationPage(new StoreListPage());
}
}
else
{
await Navigation.RemovePopupPageAsync(loadingPage);
if (responseObj["error_code"].Value == 1)
lblError.Text = responseObj["error"];
else
lblError.Text = responseObj["message"];
errorContainer.IsVisible = true;
}
}
else
{
await DisplayAlert(Constants.APP_TITLE, "Please check your internet connection.", "OK");
}
}
async public Task<string> PostData(System.Dynamic.ExpandoObject args, string actionUrl)
{
string responseData = "";
HttpClient client = new HttpClient();
client.MaxResponseContentBufferSize = 256000;
var param = Constants.JWT ? GetJWTToken(args, actionUrl) : JsonConvert.SerializeObject(args);
var content = new StringContent(param, Encoding.UTF8, "application/json");
client.DefaultRequestHeaders.Add("Authorization", param);
client.DefaultRequestHeaders.Add("X-Device-Type", "android");
client.DefaultRequestHeaders.Add("X-APP-Type", "b2b");
client.DefaultRequestHeaders.Add("X-APP-Platform", "xamarin");
HttpResponseMessage response = null;
response = await client.PostAsync(Constants.BaseUrl + actionUrl, content);
if (response.IsSuccessStatusCode)
{
response.EnsureSuccessStatusCode();
}
responseData = await response.Content.ReadAsStringAsync();
if (Constants.JWT)
{
var resp = JObject.Parse(responseData);
var respToken = resp["token"];
var rtokenStr = respToken.ToObject<String>();
var respPayloadStr = rtokenStr.Split('.');
byte[] data = JWTLibrary.Converter.Base64UrlDecode(respPayloadStr[1]);
responseData = JWTLibrary.Converter.GetStringFromBytes(data);
}
return responseData;
}
private string GetJWTToken(System.Dynamic.ExpandoObject args, string actionUrl)
{
var dt = DateTime.Now;
var ticks = dt.Ticks;
var currentSec = ticks / TimeSpan.TicksPerSecond;
var newEndTime = currentSec + 60;
Object payload = new Dictionary<string, object>()
{
{ "iat", currentSec },
{ "nbf", currentSec },
{ "exp", newEndTime },
{ "iss", actionUrl },
{ "jti", "" },
{ "bat_data", args }
};
var secret_key = "key";
dynamic n_header = new System.Dynamic.ExpandoObject();
n_header.typ = "jwt";
n_header.alg = "HS256";
byte[] headerBytes = JWTLibrary.Converter.GetBytesFromString(JsonConvert.SerializeObject(n_header));
byte[] payloadBytes = JWTLibrary.Converter.GetBytesFromString(JsonConvert.SerializeObject(payload));
var enc_header = JWTLibrary.Converter.Base64UrlEncode(headerBytes);
var enc_payload = JWTLibrary.Converter.Base64UrlEncode(payloadBytes);
string jwt_token = enc_header + "." + enc_payload;
var sh_h256 = JWTLibrary.Converter.CreateToken(jwt_token, secret_key);
var jwt_enc_signature = JWTLibrary.Converter.Base64UrlEncode(sh_h256);
jwt_token = jwt_token + "." + jwt_enc_signature;
return jwt_token;
}
答案 0 :(得分：1)
我担心问题是由dynamic关键字引起的。
DynamicMethod类是驻留在System.Reflection.Emit的运行时代码生成功能集的一部分。但是，System.Reflection.EmitAPI在iOS中不可用。
详情请参阅Why can’t I use the “dynamic” C# keyword in Xamarin.iOS?